Current Research

I am interested in the multi-scale processes affecting the health and function of forested and mixed-use landscapes, and I have focused on three research avenues falling under this broader theme. First, I am investigating the spatial-temporal dynamics and impacts of disturbance by forest insect defoliators, using a combination of remote sensing, pattern analysis, and simulation modeling. Second, I am investigating interactions between natural and human processes as they influence fire dynamics. This research includes analyses of modern fire databases in the upper Midwest, and the simulation of fire disturbance patterns as influenced by human activities, forest management, and insect disturbances. Third, I am working with Canadian scientists to develop a multi-scale toolkit approach to providing information for sustainable forest management across diverse ecological and socioeconomic systems.

Research Interests

I will continue to pursue our understanding of the drivers underlying spatial patterns of insect disturbances, employing technologies from other disciplines including molecular techniques and atmospheric modeling. The effect of climate change on insect disturbance regimes is another key area of research I wish to pursue. Finally, I am interested in how human development patterns will interact with forest disturbances and other ecosystem processes at decade to century time scales.

Why This Research is Important

Insects cause more economic damage to forest resources in the conterminous United States than any other disturbance, but our understanding of the landscape-scale factors affecting their dynamics is poorly understood. Insight into landscape pattern interacts with the dynamics of forest pests can lead to the design of pest-resistant landscapes through forest management. We also know that humans have enormous influence over the structure and character of our forested land base. Understanding how forested systems respond to human processes will allow managers to better balance multiple and sometimes conflicting objectives for our public lands (e.g., biodiversity, recreation, public safety, water quality, etc.). This new complexity in land management also requires effective decision support tools to enable land managers to make better strategic decisions based on the best available science.

National Research Highlights

The American chestnut tree is fast growing, somewhat tolerant of shade, and its wood is resistant to decay. The chestnut tree might be capable of significantly increasing carbon storage if it could be restored to its former dominance across the eastern U.S., but is it capable of reasserting its dominance in the face of changing climate and new insect pests and can it increase carbon storage in eastern forests?

The loss of top predators may have unintended consequences for forest composition and function. Forest Service scientists partnered with the U.S. Geologic Survey and National Park Service to investigate the effects of alternative wolf predation scenarios on the moose and forest dynamics at Isle Royale National Park near Michigan’s border with Canada. Will the impending loss of wolves from the park affect the future state of the forest ecosystem?

Quantifying fire severity is critical to understanding the ecosystem impacts of wildfire. Forest Service research demonstrates the magnitude of ecosystem impacts from large wildfires, the challenges of relating those impacts to repeatable and scalable fire severity indices, and the application of remote sensing to help scale severity and ecosystem impacts of large wildfires.

Simulation models of landscape disturbances have proliferated and matured. A Forest Service scientist co-edited the book “Simulation Modeling of Forest Landscape Disturbances” that represents a synthesis of the current state of knowledge in forest landscape disturbance models across a wide variety of processes that include physical (drought, wind, and fire), biological (defoliating insects, bark beetles, and tree pathogens) and human-caused activities, interactions between disturbances and climate change, and subsequent landscape recovery. Contributing authors applied models across these different dimensions to explore advancements and challenges in modeling techniques and identify future needs in quantifying forest landscape disturbances.

A Forest Service scientist led an international team to investigate how different historic forest management practices have affected spruce budworm outbreaks in a large “experimental landscape” spanning the U.S.-Canadian border. Their results show the strongest evidence to date that human-mediated changes to forest landscapes affect the intensity and consequences of forest insect outbreaks at broad spatial scales.

The results from 20 years of forest bird monitoring in four national forests in Minnesota and Wisconsin show positive trends in breeding bird population stability. The new report by Forest Service scientists and partners represents the most comprehensive volume of quantitative information ever compiled on the trends, habitat use, and community assemblages of breeding forest birds of the western Great Lakes region.

The researchers scaled up a high-profile 11-year ecosystem experiment called Aspen-FACE to assess how elevated carbon dioxide and ozone levels might impact real forests at the landscape scale over the course of many future decades. They determined that there will be winners and losers among species and within species groups but that managers can have considerable control over the outcomes by managing disturbance effects on forests and landscape spatial patterns. The researchers also found that changes will be gradual and that few species are likely to disappear completely because of carbon dioxide and ozone effects alone.